Local environmentalists — including, notably, Marblehead state Rep. Lori Ehrlich — have been pushing for years to get National Grid and other utilities to plug the tens of thousands of small gas leaks throughout the state. They’ve made some progress, but not nearly enough.

So organizations like Salem Alliance for the Environment, better known as SAFE, deserve accolades for keeping this issue on the front burner. The group is sponsoring a forum Tuesday night at Salem State University called “The Hidden Costs of Salem’s Gas Leaks,” to try to educate the public and mobilize the community behind state legislation aimed at forcing utilities to do a better job.

While Salem’s event is locally focused, the problem affects the entire region. According to utility reports, Salem had 62 gas leaks at the end of 2016, which puts it better off than some of its neighbors; Peabody had 154, Marblehead 117, and Lynn 267. Elsewhere in the region Gloucester had 43 leaks last year, Lawrence 110 and Newburyport 18.

The leaks are graded on a scale of 1 to 3, with 1 being the most severe, and 3 the weakest. (Those interested in finding out where the gas leaks are in their community can consult the interactive map put together by the Cambridge-based nonprofit The Home Energy Efficiency Team at https://www.heetma.org/squeaky-leak/natural-gas-leaks-maps/)

And those numbers are just from utility reports. SAFE, which worked with Gas Safety Inc. last year to track gas leaks in Salem, identified 232 in the city. Moreover, the group correlated gas leaks with dying street trees. Their work was so convincing that Salem has halted planting of new trees in some areas until the utilities repair the leaks.

“The whole matter of gas leaks is unacceptable,” Salem City Councilor Steve Dibble said. “While this gas is coming out, it’s hurting the environment — actually killing trees throughout the city of Salem. It’s bad for humans, and it just isn’t a safe practice.”

Dibble is certainly right about the risks. Folks in Gloucester still recall the destruction of an East Main Street home that exploded when gas leaked into the basement. Many of the gas lines in the city date back to 1911.

That’s part of the problem. Repairing or replacing old or faulty lines is costly, time-consuming business.

“It’s an issue we’ve been aggressively tackling,” National Grid spokesman Bob Kievra told reporter Dustin Luca. Kievra said his company hopes to eliminate all Grade 3 leaks over the next decade.

Kievra said the work comes with a “pretty impressive” price tag. According to The Home Energy Efficiency Team, there were 16,507 active gas leaks across Massachusetts in 2016. There were 11,930 leaks that had been repaired in that time. A 2015 Harvard University study estimated the gas leaking from those faulty or broken pipes costs utilities $120 million a year.

Activists and public safety officials urge residents to report leaks, no matter how small.

“We want people to … just be really vigilant about gas leaks around their homes and houses, their buildings, places, wherever they smell gas,” SAFE’s Pat Gozemba said. “The worst thing that can happen is people get complacent about the smell of gas, and you take it for granted — because you never know when another gas leak is beginning, and that gas leak is the one that could blow.”

Right now, however, there’s little incentive to plug street leaks deemed “nonhazardous,” since the utilities just pass on the cost of the escaping gas to their customers. SAFE is backing a bill at the state Legislature to prevent charging ratepayers for that gas. It’s a sensible proposal — ratepayers shouldn’t be paying for gas that doesn’t reach their homes, most certainly when the escaped gas is killing the trees in their neighborhood. Mayor Kim Driscoll and the Salem City Council have backed those efforts, which deserve region-wide support.

This kind of advocacy will be needed to win this years-long struggle to get utilities to expedite their repairs, and we hope other voices will join in, too.